1. Field of the Invention
This invention relates in general to cargo carrying trailers and, more particularly, to a rear impact guard assembly for a trailer.
2. Summary of the Prior Art
Cargo carrying trailers for highway use are commonly elevated from the highway. As a result, it is known that automobiles and other vehicles commonly impact underneath the back structure of a trailer during rear collisions causing possible serious injury and damage to the colliding vehicles. In order to reduce the damage caused by rear collisions of trailers, recent federal regulations have been introduced requiring the presence of impact guards having defined strength characteristics to reduce both injury and damage. For example, impact guards for trailers must withstand certain minimum impact forces and to absorb energy from impact within 5 inches of plastic deformation of the impact guard as a result of collisions up to thirty miles per hour. Many known techniques for reducing damage due to rear collisions of trailers employ relatively heavy components, which do not provide optimum protection and economy of assembly and repair. With prior rear protection, damage to the structural components of the trailer as a result of rear collisions can also occur. These damaged structural components require costly and time-consuming repair in order to restore the trailer to a safe operating condition.
In the past, damaged trailers sometimes are operated with severely deformed rear components, such as bumpers, guards and the like. By being operated in such a damaged state, rear impact protection may be compromised because of which federal regulations are being considered to require the replacement of all severely deformed rear impact guards. To replace damaged rear guards, previous impact guard systems require expensive replacement and repair in order to restore the components to an optimally safe, undamaged condition.
Previous designs of impact guards further do not provide an optimally economical replacement after a trailer is subjected to a rear collision. Accordingly, it is desirable in the prior art to provide an improved impact guard assembly to be used at the rear of a trailer body to absorb the energy of rear impact without significant damage to the trailer structure.
It is, therefore, an objective of the invention to provide an improved impact guard assembly to minimize injury and damage occurring as a result of impact against the rear of a trailer body by an automobile and the like. The impact guard assembly herein disclosed includes a plurality of vertical guards and a horizontal bumper which assembly is suitably affixed for removal to the rear of the trailer. The impact guard of the invention exceeds applicable standards regarding the absorption of impact forces as prescribed by federal law. After impact the assembly herein disclosed undergoes permanent plastic deformation and may be readily replaced by an undamaged impact assembly by removal of bolts or attachment techniques. The effectiveness of the absorption of energy insures that the components of the trailer frame on which the impact guard is removably mounted are not subjected to potential damaging deformation under a large range of impact conditions. Accordingly, the invention effectively isolates the major structural components from the damaging effects of rear collisions. By protecting the major trailer components, the costs and time required for repair are greatly reduced by the invention.
The design of the rear guard assembly herein provides a lightweight structure, which is economical to manufacture because of open sections and less parts. The rear guard assembly further provides a controlled and predictable deformation as a result of impact. Ease of assembly and disassembly for repair is facilitated by convenient bolted or riveted attachment of guard assembly to the trailer frame. The rear guard assembly herein not only is affixed to the rear sill, but also to the trailer slider rails for transfer of the loads imposed by impact to provide under a structure with improved strength. The invention provides an effective technique of preventing injury and minimizing damage to a colliding vehicle and to the trailer structure apart from the rear impact assembly as compared to prior art, rear protection techniques. In addition, the rear impact assembly herein disclosed may be readily removed even in a deformed state and replaced by a new assembly for economy and convenience allowing an impacted trailer to quickly return to service.